Tophaceous Pseudogout in the Temporomandibular Joint: A case report

115 Introduction Calcium pyrophosphate dihydrate (CPPD) deposition disorder is a general term for arthritis characterized in the precipitation of CPPD crystals in joint tissues which causes various pathological symptoms. When there is deposition of sodium urate on the joints, gout develops, but pseudogout is not caused by sodium urate—CPPD crystal is deposited in the synovial fluid showing an acute gout joint-like seizure, which indicates similarity in its pathological condition to those of gout; thus, it is has been termed “pseudogout.” Moreover, pseudogout refers only to CPPD crystal deposits that have acute gout attack-like symptoms [1]. CPPD crystal deposition disorder may be nodular in form; however, there is a rare pathological condition in which crystals are deposited in lump form yet present as a mass or nodule—this is called tophaceous pseudogout, a subtype of CPPD crystal deposition disorder, which is distinguished from false gout [2, 3]. Tophaceous pseudogout is diagnosed when the joints involve a clinically detectable mass lesion showing radiographically evident tumor-like deposition of CPPD crystals [2, 4]. The most common sites of nodular pseudogout are the knee joints of the ankles and wrists, and this type of gout rarely occurs in the temporomandibular joint (TMJ) [5]. In the present study, we describe an unusual case of Tophaceous Pseudogout in the Temporomandibular Joint: A case report